Re: Streams support in Linux

Theodore Y. Ts'o
2018-08-25T20:05:27Z

On Sat, Aug 25, 2018 at 06:51:07AM -0700, Matthew Wilcox wrote:
>
> Let's go over the properties of a file stream:
>
> - It has no life independent of the file it's attached to; you can't move
> it from one file to another
> - If the file is deleted, it is also deleted
> - If the file is renamed, it travels with the file
> - If the file is copied, the copying program decides whether any named
> streams are copied along with it.
> - Can be created, deleted. Can be renamed?
> - Openable, seekable, cachable
> - Does not have sub-streams of its own
> - Directories may also have streams which are distinct from the files
> in the directory
> - Can pipes / sockets / device nodes / symlinks / ... have streams? Unclear.
> Probably not useful.

Let's *not* make the mistakes Solaris did, and don't allow an fchdirat()
into a streams directory. Let's also not allow executing
rootkits^H^H^H^H^H^H^H^H binaries as a stream. :-)

- Ted